Match 1.uses a lens to gather and focus light 2.separates starlight into wavelengths 3.pick up faint-lighted stars 4.see binary stars giant reflectors 5.see behind nebulae dust refracting telescope radio telescopes giant refractors giant reflectors spectrograph! will give ! @adryannabayjay

I wanna say it would be 1 would be A 2 would be C 3 would be D 4 would be B and 5 would be E

hope this helps

The third choice .. (:

Radon-222 or rn-222 has a half-life of 3.82 days. to determine the fraction of an original sample of rn-222 that remains unchanged after 7.646 days, we calculate the amount of rn-222 remaining after 7.646 days and divide it with the original amount. using 1 gram as a basis and using half-life calculation methods, we can determine that  0.249 or 0.25  grams of rn-222 will remain, and thus the fraction remaining is 0.25 or 1/4.